So I've been playing poker for about 18 months. I got tired of always losing to my roommates in our weekly game so I bought some books and started learning. I played some online for a while, on and off, as well as playing some live 4-8 limit here and there. I was a small loser at both. I stopped playing for about 6 months. Then I found several excellent books at the end of last year which have helped me a lot.

At the beginning of this March I started playing in a live 3-5 NL game at Muckleshoot, and I have slowly been increasing my bankroll. From my first $500 buyin, I ran it up to $3700 by april, but then slowly lost it back by about the end of may. I did learn a lot during that time, especially patience, but also I think I've improved my hand reading skills as well.
Well I didnt play for about 2 weeks, and then I went back and started playing again and have now gotten it up to $6200. I try to play tight aggressive, but at times I find myself probably driting too much onto the loose side. I generally do very well at short handed tables, as well as very passive tables. I am trying to constantly improve my play, but I often only have time to play once or twice a week. (Work, commitments, etc.)
(I have put in roughly 160 hours to date, since march)

I would like to continue to grow my bankroll and continue to improve my play on all levels. I would also like to take down a bigger tournament, or at least do very well in one. (To me a bigger tourney would be 200-1500 buyin.)
I do not spend the money I make on other things, it's strictly for poker.

Any Advice for me? I am trying very hard not to get an overly inflated view of my poker skill, because every time I do it seems I do something stupid.
I know I have improved a lot, but still have what seems an insanely long way to go to achieve even moderate success at poker.

How do I ensure that I am playing as tight as I need to on a consistent basis? How do I ensure that I am not simply being pushed around on a regular basis by better players? Does my winning sound like simple variance at 3-5NL? I dont know what variance might be at my level lol.

I only bring $1000 to the casino with me because I dont want to tilt myself out of a lot of money if I am having a bad night. I dont get tilt prone too much anymore, but I dont want to give myself a chance to do so either. If I am winning big I aways stay as long as I possibly can and I'm not afraid to play with my winnings (meaning when I'm up for a session they dont go into chip jail.)

I would love to get as much advice as possible from anyone who has been in the same boat or is in a similar one. Thanks in advance for your comments, and I will try and keep things posted and updated.